Lightmap - Leaks everywhere with proper lightmaps

Hi guys,
I really struggle with lightmaps on my modular building pieces. I am searching now for weeks for a solution. Changed parameters here and there, searched the web and there are a lot of guys having problems with lightmaps. The solution - most of the time - were a rework of the UV channel In my case, this does not work - because mine are perfectly fine I think.

Please take a look at the screenshot. As you can the result is horrible.
Some words to my setup:

I am in a cave and some gentle light comes through the roof. Some light patches here and there (Stationary directional light). The fire barrel has stationary light - also the little lamp. There is no more light in this situation.

As you can see, the same pieces work on the blue wall, but not on the peach walls. But why?
And this happens everywhere in my scene. A lot of light leaks here and strange shadows there :confused:

I hope you can help me. I am pretty desperate D:

Thanks!

Here, another good example. It’s exactly the same mesh. On the left is everything fine. The shadows are where they are should be.On the left … well. You see it.

I’ve got this issue as well, I’m guessing it has to do with the new Intensity units.

No, this can’t be the reason, because I had this before 4.19.
There is something other completely wrong :confused:

BUMP! (Sorry :confused: )

Now it gets crazy and the work of 6 months is now almost unusable.
There was light bleeding under the fire barrels, so I thought the point lights could cause the problem here, so I changed them to two spotlights… and the result is awful.

A little hint … maybe? :confused:

Okay, nevermind.
I found a solution … by changing the light build engine.

I don’t know what happens with the default one and everyone I asked didn’t know a solution, but the Luoshuang’s GPULightmass Baker fixed all of my problems. No Light Dots anymore and smooth and nice shadows ^^

https://forums.unrealengine.com/development-discussion/rendering/1460002-luoshuang-s-gpulightmass